The present invention relates to an input-output unit for serial-parallel conversion for performing mutual conversion between serial signals transmitted to and from a control system and parallel signals transmitted between various devices by interposing between the control system and a number of the various devices drive-controlled by the control system, such as electromagnetic valves, motors.
In general, when a number of various devices such as electromagnetic valves, motors are centralized-controlled, the various devices are operated with required timing by a control signal transmitted from a control system. In this case, plural devices can be readily controlled by one operation by transmitting a control signal using a serial signal from the control system.
However, in order to control the various devices by a serial signal in such a manner, it is necessary that an electronic member or the like for extracting a driving signal from the serial signal be mounted in each device and a converter for converting the serial signal into a parallel signal be provided thereon. Accordingly, it is difficult to respond on changes in the number of the devices in series.
On the other hand, there may be provided various sensors for positional sensing, operational confirmation, or the like in the devices depending on the type thereof, and in order to confirm the operational state of the device by the control system on the basis of an output signal, etc., of those sensors, it is necessary that the output signal be sequentially transmitted to the control system. The transmission by converting into a serial signal is advantageous for ready wiring rather than by wiring to the control system directly; however, the responding to changes in the number of sensors becomes a problem.
It is a technical object of the present invention to provide an input-output unit for serial-parallel signal conversion having a simple structure and being capable of controlling various devices together by a serial signal or transmitting output signals from various sensors together to a control system by converting them into serial signals.
It is another technical object of the present invention to provide an input-output unit for serial-parallel signal conversion capable of readily responding to changes in the number of various devices or sensors.
In order to solve the above-mentioned problems, an input-output unit for serial-parallel conversion according to the present invention comprises: a plurality of input-output blocks in series for inputting control signals into various devices or for transmission of output signals from the various devices; and a relay block for relaying signals between the input-output blocks and a control system, the relay block comprising a serial terminal to be connected to the control system and a signal converter for converting between serial signals transmitted to and from the control system and parallel signals transmitted to and from the input-output blocks via a multipolar joint connector to be connected to the input-output block, wherein the input-output block comprises an input-output connector for wiring to each of various devices, a multipolar male connector disposed on one coupled surface between the input-output blocks, and a multipolar female connector disposed on the other coupled surface therebetween and connected to the male connector of the adjoining input-output block or to the joint connector disposed in the relay block, and wherein the input-output connector and a terminal of the multipolar female connector are electrically connected by wiring on a printed board disposed within the input-output block while the remaining terminals in the multipolar female connector are electrically connected to terminals of the multipolar male connector.
In the input-output unit according to the present invention, each housing of the input-output blocks may be joined with each other in a state of maintaining watertightness outwardly while the input-output connector may be attached to the housing in a state of maintaining watertightness, and a required number of the input-output blocks may be detachably assembled on a mounting rail along with the relay block connected to one end of the input-output blocks and an end block connected to the other end thereof.
In the input-output unit for serial-parallel conversion having the above-mentioned structure, the relay block and the corresponding number of input-output blocks to the required number of input-output connectors are sequentially connected to each other by joining the adjoining male and female connectors together, so that the input-output unit is used by connecting each input-output connector to various devices to be controlled or various sensors for positional sensing, operational confirmation, or the like, while the control system and the serial terminal of the relay block are connected together.
When each input-output connector is connected to each kind of devices to be controlled, since a serial signal from the control system is converted to a parallel signal for each device in the signal converter of the relay block, the parallel signal in turn is transmitted to the input-output block connected to the corresponding device via the joint connector so as to be output to each device from the input-output connector, a large number of various devices can be controlled together by the serial signal.
Also, when each input-output connector is connected to each kind of sensors, since an output signal from the sensor is transmitted to the relay block via the input-output blocks so as to be output to the control system by converting it into a serial signal in the signal converter, the output signals of various sensors and so forth can be transmitted to the control system as a serial signal by combining them to one signal.
Furthermore, since the input-output blocks adjoining to each other are joined together by respective joining of the male and female connectors, the number of blocks to be connected in series can be readily changed in demand, enabling them to correspond to changes in the number of devices or sensors readily.
Also, the input-output blocks are joined together in a state of maintaining watertightness outwardly and the input-output connector is attached to the housing in a state of maintaining watertightness to thereby render the input-output unit waterproof readily.